Electronic device

ABSTRACT

An electronic device may include a semiconductor memory, and the semiconductor memory may include a free layer having a variable magnetization direction; a pinned layer having a fixed magnetization direction; and a tunnel barrier layer interposed between the free layer and the pinned layer, wherein the free layer may include: a first sublayer having a damping constant of 0.1 or less; a second sublayer having a perpendicular magnetic anisotropy energy density ranging from 1.0×104 to 1.0×108 erg/cm3; and an insertion layer interposed between the first sublayer and the second sublayer.

CROSS-REFERENCE TO RELATED APPLICATION

This patent document claims priority of Korean Patent Application No.10-2017-0114542, entitled “ELECTRONIC DEVICE” and filed on Sep. 7, 2017,which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

This patent document relates to memory circuits or devices and theirapplications in electronic devices or systems.

BACKGROUND

Recently, as electronic devices or appliances trend towardminiaturization, low power consumption, high performance,multi-functionality, and so on, there is a demand for electronic devicescapable of storing information in various electronic devices orappliances such as a computer, a portable communication device, and soon, and research and development for such electronic devices have beenconducted. Examples of such electronic devices include electronicdevices which can store data using a characteristic switched betweendifferent resistant states according to an applied voltage or current,and can be implemented in various configurations, for example, an RRAM(resistive random access memory), a PRAM (phase change random accessmemory), an FRAM (ferroelectric random access memory), an MRAM (magneticrandom access memory), an E-fuse, etc.

SUMMARY

The disclosed technology in this patent document includes memorycircuits or devices and their applications in electronic devices orsystems and various implementations of an electronic device, in which anelectronic device includes a semiconductor memory which can improvecharacteristics of a variable resistance element.

In one aspect, an electronic device may include a semiconductor memory,and the semiconductor memory may include a free layer having a variablemagnetization direction; a pinned layer having a fixed magnetizationdirection; and a tunnel barrier layer interposed between the free layerand the pinned layer, wherein the free layer may include: a firstsublayer having a damping constant of 0.1 or less; a second sublayerhaving a perpendicular magnetic anisotropy energy density ranging from1.0×10⁴ to 1.0×10⁸ erg/cm³; and an insertion layer interposed betweenthe first sublayer and the second sublayer.

Implementations of the above electronic device may include one or morethe following.

The second sublayer may be disposed closer to the tunnel barrier layerthan the first sublayer is. The first sublayer may include a Heusleralloy, a half-Heusler alloy, or a half-metal, or a combination thereof.The insertion layer may include a material blocking crystallinity thatis transferred from a layer disposed below the insertion layer. Theinsertion layer may include Zr, Hf, V, Cr, Cu, Nb, Mo, Ru, Rh, Ta, W, Reor Ir, or a combination thereof. The second sublayer may include analloy or a stack structure, which includes Co, Fe or B, or a combinationthereof. The second sublayer may include a Co—Fe—B alloy or a Co—Fe—B—Xalloy (where X may be Mn, Cu, Al, Si, Ti, V, Cr, Ni, Ga, Ge, Zr, Nb, Mo,Pd, Ag, Hf, Ta, W or Pt). The first sublayer may have a damping constantranging from 0.001 to 0.1.

The electronic device may further include a microprocessor whichincludes: a control unit configured to receive a signal including acommand from an outside of the microprocessor, and performs extracting,decoding of the command, or controlling input or output of a signal ofthe microprocessor; an operation unit configured to perform an operationbased on a result that the control unit decodes the command; and amemory unit configured to store data for performing the operation, datacorresponding to a result of performing the operation, or an address ofdata for which the operation is performed, wherein the semiconductormemory is part of the memory unit in the microprocessor.

The electronic device may further include a processor which includes: acore unit configured to perform, based on a command inputted from anoutside of the processor, an operation corresponding to the command, byusing data; a cache memory unit configured to store data for performingthe operation, data corresponding to a result of performing theoperation, or an address of data for which the operation is performed;and a bus interface connected between the core unit and the cache memoryunit, and configured to transmit data between the core unit and thecache memory unit, wherein the semiconductor memory is part of the cachememory unit in the processor.

The electronic device may further include a processing system whichincludes: a processor configured to decode a command received by theprocessor and control an operation for information based on a result ofdecoding the command; an auxiliary memory device configured to store aprogram for decoding the command and the information; a main memorydevice configured to call and store the program and the information fromthe auxiliary memory device such that the processor can perform theoperation using the program and the information when executing theprogram; and an interface device configured to perform communicationbetween at least one of the processor, the auxiliary memory device andthe main memory device and the outside, wherein the semiconductor memoryis part of the auxiliary memory device or the main memory device in theprocessing system.

The electronic device may further include a data storage system whichincludes: a storage device configured to store data and conserve storeddata regardless of power supply; a controller configured to controlinput and output of data to and from the storage device according to acommand inputted from an outside; a temporary storage device configuredto temporarily store data exchanged between the storage device and theoutside; and an interface configured to perform communication between atleast one of the storage device, the controller and the temporarystorage device and the outside, wherein the semiconductor memory is partof the storage device or the temporary storage device in the datastorage system.

The electronic device may further include a memory system whichincludes: a memory configured to store data and conserve stored dataregardless of power supply; a memory controller configured to controlinput and output of data to and from the memory according to a commandinputted from an outside; a buffer memory configured to buffer dataexchanged between the memory and the outside; and an interfaceconfigured to perform communication between at least one of the memory,the memory controller and the buffer memory and the outside, wherein thesemiconductor memory is part of the memory or the buffer memory in thememory system.

In another aspect, an electronic device including a semiconductormemory, wherein the semiconductor memory may include a variableresistance element, wherein the variable resistance element may include:a free layer having a variable magnetization direction; a pinned layerhaving a fixed magnetization direction; and a tunnel barrier layerinterposed between the free layer and the pinned layer, wherein the freelayer may include: a first sublayer including a Heusler alloy, ahalf-Heusler alloy, or a half-metal, or a combination thereof; a secondsublayer including an alloy or a stack structure which includes Co, Feor B, or a combination thereof; and an insertion layer interposedbetween the first sublayer and the second sublayer.

Implementations of the above electronic device may include one or morethe following.

The first sublayer may be structured to decrease a damping constant ofthe free layer. The second sublayer may be structured to maintain aperpendicular magnetic anisotropy energy density of the free layer at ahigh level. The insertion layer may include a material blockingcrystallinity that is transferred from a layer disposed below theinsertion layer. The insertion layer may include Zr, Hf, V, Cr, Cu, Nb,Mo, Ru, Rh, Ta, W, Re or Ir, or a combination thereof. The secondsublayer may include a Co—Fe—B alloy or a Co—Fe—B—X alloy (where, X maybe Mn, Cu, Al, Si, Ti, V, Cr, Ni, Ga, Ge, Zr, Nb, Mo, Pd, Ag, Hf, Ta, Wor Pt). The first sublayer may have a damping constant ranging from0.001 to 0.1.

These and other aspects, implementations and associated advantages aredescribed in greater detail in the drawings, the description and theclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view illustrating a variable resistanceelement having a free layer with a single-layer structure.

FIG. 2 is a cross-sectional view illustrating an exemplary variableresistance element in accordance with an implementation of the disclosedtechnology.

FIG. 3 is a cross-sectional view illustrating an exemplary memory deviceand a method for fabricating the same in accordance with animplementation of the disclosed technology.

FIG. 4 is a cross-sectional view illustrating another exemplary memorydevice and a method for fabricating the same in accordance with animplementation of the disclosed technology.

FIG. 5 is an example of configuration diagram of a microprocessorimplementing memory circuitry based on an implementation of thedisclosed technology.

FIG. 6 is an example of configuration diagram of a processorimplementing memory circuitry based on an implementation of thedisclosed technology.

FIG. 7 is an example of configuration diagram of a system implementingmemory circuitry based an implementation of the disclosed technology.

FIG. 8 is an example of configuration diagram of a data storage systemimplementing memory circuitry based on an implementation of thedisclosed technology.

FIG. 9 is an example of configuration diagram of a memory systemimplementing memory circuitry based on an implementation of thedisclosed technology.

DETAILED DESCRIPTION

Various examples and implementations of the disclosed technology aredescribed below in detail with reference to the accompanying drawings.

The drawings may not be necessarily to scale and in some instances,proportions of at least some of substrates in the drawings may have beenexaggerated in order to clearly illustrate certain features of thedescribed examples or implementations. In presenting a specific examplein a drawing or description having two or more layers in a multi-layersubstrate, the relative positioning relationship of such layers or thesequence of arranging the layers as shown reflects a particularimplementation for the described or illustrated example and a differentrelative positioning relationship or sequence of arranging the layersmay be possible.

Prior to explaining implementations of the present disclosure, avariable resistance element in accordance with a comparative examplewill be explained.

FIG. 1 is a cross-sectional view illustrating a variable resistanceelement having a free layer with a single-layer structure.

Referring to FIG. 1, a variable resistance element 10 may include aMagnetic Tunnel Junction (MTJ) structure which includes a free layer 12having a variable magnetization direction, a pinned layer 14 having afixed magnetization direction and a tunnel barrier layer 13 interposedbetween the free layer 12 and the pinned layer 14.

The resistance in the electrical path across the MTJ structure exhibitsa variable resistance with different resistance values depending on therelative direction between the magnetization directions of the freelayer 12 and the pinned layer 14 on two sides of the tunnel barrierlayer 13. The free layer 12 is structured to exhibit a variablemagnetization direction that can be changed to produce differentmagnetization states for the MTJ structure and may also be referred toas a storage layer.

The pinned layer 14 is structured to exhibit a fixed magnetizationdirection and may also be referred to as a reference layer. The freelayer 12 and the pinned layer 14 may have a single-layer structure or amulti-layer structure that includes magnetic materials. The tunnelbarrier layer 13 is interposed between the free layer 12 and the pinnedlayer 14 to allow the tunneling of electrons in both data reading anddata writing operations. The tunnel barrier layer 13 may include aninsulating oxide. The resistance in the electrical path across the MTJstructure exhibits a variable resistance with different resistancevalues depending on the relative direction between the magnetizationdirections of the free layer 12 and the pinned layer 14 on two sides ofthe tunnel barrier layer 13. Accordingly, the magnetization direction ofthe free layer 12 can be controlled to set the MTJ structure to exhibitdifferent resistance values for storing different digital data. Thechange in the magnetization direction of the free layer 12 may beinduced by spin transfer torque via a spin-polarized current that isdirected to flow through the tunnel barrier layer 13 via the electrontunneling. In a read operation, a small read current is directed throughthe MTJ structure that does not change the magnetization direction ofthe free layer 12 to enable readout the resistance value of the MTJstructure at a given magnetization direction of the free layer 12. In awrite operation, a sufficiently large spin-polarized write current isdirected through the MTJ structure to produce a sufficiently high spintransfer torque to change the existing magnetization direction of thefree layer 12, thus writing a new magnetization state in the MTJstructure.

In some implementations such as the example shown, the variableresistance element 10 may further include one or more additional layersto improve characteristics of the MTJ structure. For example, thevariable resistance element 10 may further include an under layer 11disposed below the MTJ structure, or an upper layer 15 disposed over theMTJ structure, or others.

To provide a high density memory device including the variableresistance element 10, the variable resistance element 10 can bedesigned to reduce a switching current that can change a magnetizationdirection of the free layer 12. This is because the size of each memorycell containing the variable resistance element 10 is dependent on thesize of a transistor within the cell for supplying the switching currentand the size of the transistor can be reduced when the switching currentis reduced (e.g., due to the reduced need for heat dissipation). In thisregard, the switching current is proportional to a damping constant α ofthe free layer 12 so that the damping constant α of the free layer 12may be lowered in order to reduce the switching current, achieving thehigh-density of the variable resistance element 10. Accordingly, as thedamping constant α of the free layer 12 becomes lower, the magnetizationdirection of the free layer 12 can be easily changed with a smallercurrent, thereby improving characteristics of the variable resistanceelement 10. However, there are limitations to reduction of the dampingconstant of the free layer. This is because, if the free layer 12 isformed of or includes a material having a low damping constant, theperpendicular magnetic anisotropy at an interface between the free layer12 and the tunnel barrier layer 13 may be decreased to causedeterioration of the characteristics of the variable resistance element10. Therefore, in designing the variable resistance element 10, on onehand, there is a need to reduce the switching current for reducing thesize of the variable resistance element 10 for a high density memorychip but, on the other hand, there is a need not to reduce the dampingconstant to a low level that would adversely affect the perpendicularmagnetic anisotropy. The disclosed technology in this document balancesthe above two competing needs achieve a high density memory chip withdesired reliable memory operation performance.

In accordance with an implementation of the disclosed technology, asemiconductor memory and its fabricating method are provided to achievedesired characteristics of the variable resistance element, for example,by including a free layer having a multi-layer structure which iscapable of maintaining a high perpendicular magnetic anisotropy energydensity (Ku) value while significantly decreasing a damping constant andthus, lowering a switching current.

FIG. 2 is a cross-sectional view illustrating an exemplary variableresistance element in accordance with an implementation of the disclosedtechnology.

Referring to FIG. 2, a variable resistance element 100 may include amagnetic tunnel junction (MTJ) structure which includes a free layer130, a pinned layer 150 and a tunnel barrier layer 140.

The free layer 130, the pinned layer 150, and the tunnel barrier layer140 collectively form part of an MTJ structure exhibiting variableresistance values for storing different data bits as explained above.The free layer 130 has a variable magnetization direction, the pinnedlayer 150 has a fixed magnetization direction, and the tunnel barrierlayer 140 is interposed between the free layer 130 and the pinned layer150 to allow the tunneling of electrons in both data reading and datawriting operations.

The free layer 130 may have a variable magnetization direction thatchanges between different directions to cause the MTJ structure to havea variable resistance value. With the change of the magnetizationdirection of the free layer 130, the relative relationship of themagnetization directions of the free layer 130 and the pinned layer 150also changes, which allows the variable resistance element 100 to storedifferent data or represent different data bits. The free layer 130 mayalso be referred as a storage layer or the like. The magnetizationdirection of the free layer 130 may be substantially perpendicular to asurface of the free layer 130, the tunnel barrier layer 140 and thepinned layer 150. In other words, the magnetization direction of thefree layer 130 may be substantially parallel to the stacking directionsof the free layer 130, the tunnel barrier layer 140 and the pinned layer150. Therefore, the magnetization direction of the free layer 130 may bechanged between a downward direction and an upward direction. The changein the magnetization direction of the free layer 130 may be induced byspin transfer torque.

The free layer 130 may have a multi-layer structure.

In an implementation, the free layer 130 may include a first sublayer132, an insertion layer 134 and a second sublayer 136. The firstsublayer 132 is disposed far from the tunnel barrier layer 140 and thesecond sublayer 136 is disposed adjacent to the tunnel barrier layer140. The second sublayer 136 is disposed closer to the tunnel barrierlayer 140 than the first sublayer 132 is. In some implementations, thesecond sublayer 136, the insertion layer 134, and the first sublayer 132are disposed in order along a downward direction.

The first sublayer 132 may include a material having a low dampingconstant α. In an implementation, the first sublayer 132 may have a lowdamping constant α of 0.1 or less. In another implementation, the firstsublayer 132 may have a low damping constant α ranging from 0.001 to0.1. When the first sublayer 132 has a low damping constant α of 0.1 orless, a magnetization direction of the free layer 12 can be easilychanged with a smaller current, thereby improving characteristics of thevariable resistance element 100.

The first sublayer 132 may include a Heusler alloy, a half-Heusleralloy, or a half-metal, or a combination thereof.

The Heusler alloy or the half-Heusler alloy is a magnetic intermetallicwith a face-centered cubic crystal structure. The Heusler alloy may havea composition of X₂YZ and the half-Heusler alloy may have a compositionof XYZ, where X and Y are transition metals and Z is in the p-block. TheHeusler alloy or the half-Heusler alloy may exhibit properties that areassociated with the intrinsic spin of electrons in addition toelectronic charge, which are referred to as spintronics. The examples ofthe properties relevant to spintronics may include magnetoresistance,variations of the Hall effect, ferromagnetism, antiferromagnetism,ferrimagnetism, halfmetallicity, semimetallicity, semiconductivity withspin filter ability, superconductivity, or topological insulation. Themagnetism of the Heusler alloy or the half-Heusler alloy may result froma double-exchange mechanism between neighboring magnetic ions.

Examples of the Heusler alloy may include Cu₂MnAl, Cu₂MnIn, Cu₂MnSn,Ni₂MnAl, Ni₂MnIn, Ni₂MnSn, Ni₂MnSb, Ni₂MnGa, Co₂MnAl, Co₂MnSi, Co₂MnGa,Co₂MnGe, Co₂NiGa, Pd₂MnAl, Pd₂MnIn, Pd₂MnSn, Pd₂MnSb, Co₂FeSi, Co₂FeAl,Fe₂VAl, Mn₂VGa, or Co₂FeGe. The examples of the Heusler alloy are notlimited to those above and may include others.

The half-metal may be or include any substance that acts as a conductorto electrons of one spin orientation, but as an insulator orsemiconductor to the electrons of the opposite spin orientation. Allhalf-metals are ferromagnetic or ferrimagnetic, and examples of thehalf-metals may be or include oxides, sulfides, or Heusler alloys.

Examples of the half-metal may include chromium (IV) oxide, magnetite,lanthanum strontium manganite (LSMO), or chromium arsenide, or others.

The first sublayer 132 is formed of or includes a material with a lowdamping constant α to decrease a switching current, thereby improvingcharacteristics of the variable resistance element 100.

The insertion layer 134 may block crystallinity that can be transferredfrom the first sublayer 132 to layers disposed over the first sublayer132.

Therefore, the insertion layer 134 may include a material capable ofblocking crystallinity that is transferred from any layer below theinsertion layer 134. In an implementation, the insertion layer 134 mayinclude a metal such as Zr, Hf, V, Cr, Cu, Nb, Mo, Ru, Rh, Ta, W, Re, orIr, or a combination thereof.

The second sublayer 136 may include a material having a highperpendicular magnetic anisotropy energy density (Ku). In animplementation, the second sublayer 136 may have a perpendicularmagnetic anisotropy energy density (Ku) ranging from 1.0×10⁴ to 1.0×10⁸erg/cm³. When the second sublayer 136 has a high perpendicular magneticanisotropy energy density (Ku) ranging from 1.0×10⁴ to 1.0×10⁸ erg/cm³,it is possible to maintain a sufficiently high perpendicular magneticanisotropy the free layer 130 in order to exhibit an improvedcharacteristics of the variable resistance element 100.

The second sublayer 136 may include an alloy including Co, Fe or B, forexample, a Co—Fe—B alloy, a Co—Fe—B—X alloy (where, X may be Mn, Cu, Al,Si, Ti, V, Cr, Ni, Ga, Ge, Zr, Nb, Mo, Pd, Ag, Hf, Ta, W or Pt), anFe—Pt alloy, an Fe—Pd alloy, a Co—Pd alloy, a Co—Pt alloy, a Co—Gdalloy, an Fe—Ni—Pt alloy, a Co—Fe—Pt alloy, a Co—Ni—Pt alloy, or aCo—Fe—Pd alloy or others, a stack structure such as Co/Pt, Co/Pd, Co/Ir,or Co/Ru or others, or an alternate stack structure of a magneticmaterial and a nonmagnetic material.

The second sublayer 136 may serve to maintain perpendicular magneticanisotropy of the free layer 130 at a high level.

As such, in accordance with the implementation, the first sublayer 132may be formed of or include a material having a low damping constant,the second sublayer 136 may be formed of or include a material having ahigh perpendicular magnetic anisotropy energy density (Ku), and theinsertion layer 134 capable of blocking crystallinity that istransferred from the layer(s) disposed below the insertion layer 134 maybe formed between the first sublayer 132 and the second sublayer 136. Byforming the free layer 130 in a multi-layer structure, the free layer130 can have a damping constant not higher than 0.1 and a highperpendicular magnetic anisotropy between 1.0×10⁴ to 1.0×10⁸ erg/cm³.Since the free layer 130 includes the first sublayer 132 with a dampingconstant lower than that of the free layer 12 in FIG. 1, a switchingcurrent can be decreased as compared to the variable resistance element10 in FIG. 1. In addition, since the free layer 130 includes the secondsublayer 136 with a high perpendicular magnetic anisotropy as comparedto the free layer 12 in FIG. 1, it is also possible to overcome aproblem caused by using a material for the free layer with a low dampingconstant, for example, a decrease in a perpendicular magnetic anisotropyenergy density (Ku) at an interface between the free layer 130 and thetunnel barrier layer 140. Therefore, the free layer 130 can achieve botheffects of reducing a drive current of the variable resistance element100 and improving perpendicular magnetic anisotropy of the variableresistance element 100.

The tunnel barrier layer 140 may allow the tunneling of electrons inboth data reading and data writing operations. In a write operation forstoring new data, a high write current may be directed through thetunnel barrier layer 140 to change the magnetization direction of thefree layer 130 and thus to change the resistance state of the MTJ forwriting a new data bit. In a reading operation, a low reading currentmay be directed through the tunnel barrier layer 140 without changingthe magnetization direction of the free layer 130 to measure theexisting resistance state of the MTJ under the existing magnetizationdirection of the free layer 130 to read the stored data bit in the MTJ.The tunnel barrier layer 140 may include a dielectric oxide, forexample, an oxide of a material such as Mg, Al, Ca, Sr, Ti, V, Nb, Y,Zn, or Sn or others, or a mixed oxide thereof.

The pinned layer 150 may have a pinned magnetization direction whichcontrasts with the magnetization direction of the free layer 130, andmay be referred to as a reference layer or the like. In someimplementations, the magnetization direction of the pinned layer 150 maybe pinned in a downward direction. In some implementations, themagnetization direction of the pinned layer 150 may be pinned in anupward direction.

The pinned layer 150 may have a single-layer or multilayer structureincluding a ferromagnetic material. For example, the pinned layer 150may include an alloy based on Fe, Ni or Co, for example, an Fe—Pt alloy,an Fe—Pd alloy, a Co—Pd alloy, a Co—Pt alloy, an Fe—Ni—Pt alloy, aCo—Fe—Pt alloy, a Co—Ni—Pt alloy, or a Co—Fe—B alloy or others, or mayinclude a stack of metals, such as Co/Pt, or Co/Pd or others.

The magnetization directions of the free layer 130 and the pinned layer150 may be substantially perpendicular to an interface of the layers,for example, an interface between the free layer 130 and the tunnelbarrier layer 140. In some implementation, the variable resistanceelement 100 may include a perpendicular MTJ structure.

The variable resistance element 100 may store data by switching betweendifferent resistance states according to a voltage or current applied tothe variable element 100. If a voltage or current is applied to thevariable resistance element 100, the magnetization direction of the freelayer 130 may be changed by spin torque transfer. When the magnetizationdirections of the free layer 130 and the pinned layer 150 are parallelto each other, the variable resistance element 100 may be in a lowresistance state to store a designated digital data bit such as ‘0’.Conversely, when the magnetization directions of the free layer 130 andthe pinned layer 150 are anti-parallel to each other, the variableresistance element 100 may be in a high resistance state to store adesignated digital data bit such as ‘1’. In some implementations, thevariable resistance element 100 can be configured to store data bit ‘1’when the magnetization directions of the free layer 130 and the pinnedlayer 150 are parallel to each other and to store data bit ‘0’ when themagnetization directions of the free layer 130 and the pinned layer 150are anti-parallel to each other.

In some implementations, the variable resistance element 100 may furtherinclude one or more layers performing various functions to improve acharacteristic of the MTJ structure. For example, the variableresistance element 100 may further include a buffer layer 110, an underlayer 120, a spacer layer 160, a magnetic correction layer 170 and acapping layer 180.

The buffer layer 110 may be disposed under the under layer 120 and aidin crystal growth of the under layer 120. When the buffer layer 110 isformed under the under layer 120, it is possible to aid in crystalgrowth of the under layer 120 and thus improve perpendicular magneticcrystalline anisotropy of the free layer 130′. The buffer layer 110 mayhave a single-layer or multilayer structure including a metal, a metalalloy, a metal nitride, or a metal oxide, or a combination thereof.

The under layer 120 may be disposed under the free layer 130′ and serveto improve perpendicular magnetic crystalline anisotropy of the freelayer 130.

The under layer 120 may have a single-layer or multilayer structureincluding a metal, a metal alloy, a metal nitride, or a metal oxide, ora combination thereof.

The magnetic correction layer 170 may serve to offset the effect of thestray magnetic field produced by the pinned layer 150. In this case, theeffect of the stray magnetic field of the pinned layer 150 can decrease,and thus a biased magnetic field in the free layer 130′ can decrease.The magnetic correction layer 170 may have a magnetization directionanti-parallel to the magnetization direction of the pinned layer 150. Inthe implementation, when the pinned layer 150 has a downwardmagnetization direction, the magnetic correction layer 170 may have anupward magnetization direction. Conversely, when the pinned layer 150has an upward magnetization direction, the magnetic correction layer 170may have a downward magnetization direction. The magnetic correctionlayer 170 may have a single-layer or multilayer structure including aferromagnetic material.

In this implementation, the magnetic correction layer 170 is locatedabove the pinned layer 150, but the position of the magnetic correctionlayer 170 may be changed. For example, the magnetic correction layer 170may also be located above, below, or next to the MTJ structure while itis patterned separately from the MTJ structure.

The spacer layer 160 may be interposed between the magnetic correctionlayer 170 and the pinned layer 150 and function as a buffer between themagnetic correction layer 170 and the pinned layer 150. The spacer layer160 may serve to improve characteristics of the magnetic correctionlayer 170. The spacer layer 160 may include a noble metal such asruthenium (Ru).

The capping layer 180 may function as a hard mask for patterning thevariable resistance element 100. In some implementations, the cappinglayer 180 may include various conductive materials such as a metal. Insome implementations, the capping layer 180 may include a metallicmaterial having almost none or a small number of pin holes and highresistance to wet and/or dry etching. In some implementations, thecapping layer 180 may include a metal, a nitride or an oxide, or acombination thereof. For example, the capping layer 180 may include anoble metal such as ruthenium (Ru).

In some implementations, the positions of the free layer 130 and thepinned layer 150 with respect to the tunnel barrier layer 140 may bechanged with each other. For example, the free layer 130 may be disposedon the tunnel barrier layer 140 and the pinned layer 150 may be disposedunder the tunnel barrier layer 140 and over the buffer layer 110.

A semiconductor memory device as disclosed in this document may includea cell array of variable resistance elements 100 to store data. Thesemiconductor memory may further include various components such aslines, elements, etc. to drive or control each variable resistanceelement 100. This is exemplarily explained with reference to FIGS. 3 and4.

FIG. 3 is a cross-sectional view for explaining a memory device and amethod for fabricating the same in accordance with an implementation ofthe disclosed technology.

Referring to FIG. 3, the memory device of the implementation may includea substrate 300, lower contacts 320 formed over the substrate 300,variable resistance elements 100 formed over the lower contacts 320 andupper contacts 350 formed over the variable resistance element 100. Foreach variable resistance element 100, a specific structure as a switchor switching circuit/element, for example, a transistor, for controllingan access to a particular variable resistance element 100 can beprovided over the substrate 300 to control the variable resistanceelement 100, where the switch can be turned on to select the variableresistance element 100 or turned off to de-select the variableresistance element 100. The lower contacts 320 may be disposed over thesubstrate 300, and couple a lower end of the variable resistance element100 to a portion of the substrate 300, for example, a drain of thetransistor as the switching circuit for the variable resistance element100. The upper contact 350 may be disposed over the variable resistanceelement 100, and couple an upper end of the variable resistance element100 to a certain line (not shown), for example, a bit line. In FIG. 3,two variable resistance elements 100 are shown as examples of theelements in an array of variable resistance elements 100.

The above memory device may be fabricated by following processes.

First, the substrate 300 in which the transistor or the like is formedmay be provided, and then, a first interlayer dielectric layer 310 maybe formed over the substrate 300. Then, the lower contact 320 may beformed by selectively etching the first interlayer dielectric layer 310to form a hole H exposing a portion of the substrate 300 and filling thehole H with a conductive material. Then, the variable resistance element100 may be formed by forming material layers for the variable resistanceelement 100 over the first interlayer dielectric layer 310 and the lowercontact 320, and selectively etching the material layers. The etchprocess for forming the variable resistance element 100 may include theIBE method which has a strong physical etching characteristic. Then, asecond interlayer dielectric layer 330 may be formed to cover thevariable resistance element. Then, a third interlayer dielectric layer340 may be formed over the variable resistance element 100 and thesecond interlayer dielectric layer 330, and then upper contacts 350passing through the third interlayer dielectric layer 340 and coupled toan upper end of the variable resistance element 100 may be formed.

In the memory device in accordance with this implementation, all layersforming the variable resistance element 100 may have sidewalls which arealigned with one another. That is because the variable resistanceelement 100 is formed through an etch process using one mask.

Unlike the implementation of FIG. 3, a part of the variable resistanceelement 100 may be patterned separately from other parts. This processis illustrated in FIG. 4.

FIG. 4 is a cross-sectional view for explaining a memory device and amethod for fabricating the same in accordance with anotherimplementation of the disclosed technology. The following descriptionswill be focused on a difference from the implementation of FIG. 3.

Referring to FIG. 4, the memory device in accordance with thisimplementation may include a variable resistance element 100 of whichparts, for example, a buffer layer 110 and a under layer 120, havesidewalls that are not aligned with other layers thereof. As shown inFIG. 4, the buffer layer 110 and the under layer 120 may have sidewallswhich are aligned with lower contacts 420.

The memory device in FIG. 4 may be fabricated by following processes.

First, a first interlayer dielectric layer 410 may be formed over asubstrate 400, and then selectively etched to form a hole H exposing aportion of the substrate 400. The, the lower contacts 420 may be formedto fill a lower portion of the hole H. For example, the lower contacts420 may be formed through a series of processes of forming a conductivematerial to cover the resultant structure having the hole formedtherein, and removing a part of the conductive material through an etchback process or the like until the conductive material has a desiredthickness. Then, the buffer layer 110 and an under layer 120 may beformed so as to fill the remaining portion the hole H. For example, thebuffer layer 110 may be formed by forming a material layer for formingthe buffer layer 110 which covers the resultant structure in which thelower contacts 420 is formed, and then removing a portion of thematerial layer by, for example, an etch-back process until the materiallayer has a desired thickness. Moreover, the under layer 120 may beformed by forming a material layer for forming the under layer 120 whichcovers the resultant structure in which the lower contacts 420 and thebuffer layer 110 are formed, and then performing a planarization processsuch as a CMP (Chemical Mechanical Planarization) until a top surface ofthe first interlayer dielectric layer 410 is exposed. Then, theremaining parts of the variable resistance element 100 may be formed byforming material layers for forming the remaining layers of the variableresistance element 100 except the buffer layer 110 and the under layer120 over the lower contacts 420 and the first interlayer dielectriclayer 410.

Subsequent processes are substantially the same as those as shown inFIG. 3.

In this implementation, the height which needs to be etched at a time inorder to form the variable resistance element 100 can be reduced, whichmakes it possible to lower the difficulty level of the etch process.

Although in this implementation, the buffer layer 110 and the underlayer 120 are buried in the hole H, other parts of the variableresistance element 100 may also be buried as needed.

The above and other memory circuits or semiconductor devices based onthe disclosed technology can be used in a range of devices or systems.FIGS. 5 to 9 provide some examples of devices or systems that canimplement the memory circuits disclosed herein.

FIG. 5 is an example of configuration diagram of a microprocessorimplementing memory circuitry based on an implementation of thedisclosed technology.

Referring to FIG. 5, a microprocessor 1000 may perform tasks forcontrolling and tuning a series of processes of receiving data fromvarious external devices, processing the data, and outputting processingresults to external devices. The microprocessor 1000 may include amemory unit 1010, an operation unit 1020, a control unit 1030, and soon. The microprocessor 1000 may be various data processing units such asa central processing unit (CPU), a graphic processing unit (GPU), adigital signal processor (DSP) and an application processor (AP).

The memory unit 1010 is a part which stores data in the microprocessor1000, as a processor register, register or the like. The memory unit1010 may include a data register, an address register, a floating pointregister and so on. Besides, the memory unit 1010 may include variousregisters. The memory unit 1010 may perform the function of temporarilystoring data for which operations are to be performed by the operationunit 1020, result data of performing the operations and addresses wheredata for performing of the operations are stored.

The memory unit 1010 may include one or more of the above-describedsemiconductor devices in accordance with the implementations. Forexample, the memory unit 1010 may include a free layer having a variablemagnetization direction; a pinned layer having a fixed magnetizationdirection; and a tunnel barrier layer interposed between the free layerand the pinned layer, wherein the free layer may include: a firstsublayer having a damping constant of 0.1 or less; a second sublayerhaving a perpendicular magnetic anisotropy energy density ranging from1.0×10⁴ to 1.0×10⁸ erg/cm³; and an insertion layer interposed betweenthe first sublayer and the second sublayer. Through this, data storagecharacteristics of the memory unit 1010 may be improved. As aconsequence, operating characteristics of the microprocessor 1000 may beimproved.

The operation unit 1020 may perform four arithmetical operations orlogical operations according to results that the control unit 1030decodes commands. The operation unit 1020 may include at least onearithmetic logic unit (ALU) and so on.

The control unit 1030 may receive signals from the memory unit 1010, theoperation unit 1020 and an external device of the microprocessor 1000,perform extraction, decoding of commands, and controlling input andoutput of signals of the microprocessor 1000, and execute processingrepresented by programs.

The microprocessor 1000 according to this implementation mayadditionally include a cache memory unit 1040 which can temporarilystore data to be inputted from an external device other than the memoryunit 1010 or to be outputted to an external device. In this case, thecache memory unit 1040 may exchange data with the memory unit 1010, theoperation unit 1020 and the control unit 1030 through a bus interface1050.

FIG. 6 is an example of configuration diagram of a processorimplementing memory circuitry based on an implementation of thedisclosed technology.

Referring to FIG. 6, a processor 1100 may improve performance andrealize multi-functionality by including various functions other thanthose of a microprocessor which performs tasks for controlling andtuning a series of processes of receiving data from various externaldevices, processing the data, and outputting processing results toexternal devices. The processor 1100 may include a core unit 1110 whichserves as the microprocessor, a cache memory unit 1120 which serves tostoring data temporarily, and a bus interface 1130 for transferring databetween internal and external devices. The processor 1100 may includevarious system-on-chips (SoCs) such as a multi-core processor, a graphicprocessing unit (GPU) and an application processor (AP).

The core unit 1110 of this implementation is a part which performsarithmetic logic operations for data inputted from an external device,and may include a memory unit 1111, an operation unit 1112 and a controlunit 1113.

The memory unit 1111 is a part which stores data in the processor 1100,as a processor register, a register or the like. The memory unit 1111may include a data register, an address register, a floating pointregister and so on. Besides, the memory unit 1111 may include variousregisters. The memory unit 1111 may perform the function of temporarilystoring data for which operations are to be performed by the operationunit 1112, result data of performing the operations and addresses wheredata for performing of the operations are stored. The operation unit1112 is a part which performs operations in the processor 1100. Theoperation unit 1112 may perform four arithmetical operations, logicaloperations, according to results that the control unit 1113 decodescommands, or the like. The operation unit 1112 may include at least onearithmetic logic unit (ALU) and so on. The control unit 1113 may receivesignals from the memory unit 1111, the operation unit 1112 and anexternal device of the processor 1100, perform extraction, decoding ofcommands, controlling input and output of signals of processor 1100, andexecute processing represented by programs.

The cache memory unit 1120 is a part which temporarily stores data tocompensate for a difference in data processing speed between the coreunit 1110 operating at a high speed and an external device operating ata low speed. The cache memory unit 1120 may include a primary storagesection 1121, a secondary storage section 1122 and a tertiary storagesection 1123. In general, the cache memory unit 1120 includes theprimary and secondary storage sections 1121 and 1122, and may includethe tertiary storage section 1123 in the case where high storagecapacity is required. As the occasion demands, the cache memory unit1120 may include an increased number of storage sections. That is tosay, the number of storage sections which are included in the cachememory unit 1120 may be changed according to a design. The speeds atwhich the primary, secondary and tertiary storage sections 1121, 1122and 1123 store and discriminate data may be the same or different. Inthe case where the speeds of the respective storage sections 1121, 1122and 1123 are different, the speed of the primary storage section 1121may be largest. At least one storage section of the primary storagesection 1121, the secondary storage section 1122 and the tertiarystorage section 1123 of the cache memory unit 1120 may include one ormore of the above-described semiconductor devices in accordance with theimplementations. For example, the cache memory unit 1120 may include afree layer having a variable magnetization direction; a pinned layerhaving a fixed magnetization direction; and a tunnel barrier layerinterposed between the free layer and the pinned layer, wherein the freelayer may include: a first sublayer having a damping constant of 0.1 orless; a second sublayer having a perpendicular magnetic anisotropyenergy density ranging from 1.0×10⁴ to 1.0×10⁸ erg/cm³; and an insertionlayer interposed between the first sublayer and the second sublayer.Through this, data storage characteristics of the cache memory unit 1120may be improved. As a consequence, operating characteristics of theprocessor 1100 may be improved.

Although it was shown in FIG. 6 that all the primary, secondary andtertiary storage sections 1121, 1122 and 1123 are configured inside thecache memory unit 1120, it is to be noted that all the primary,secondary and tertiary storage sections 1121, 1122 and 1123 of the cachememory unit 1120 may be configured outside the core unit 1110 and maycompensate for a difference in data processing speed between the coreunit 1110 and the external device. Meanwhile, it is to be noted that theprimary storage section 1121 of the cache memory unit 1120 may bedisposed inside the core unit 1110 and the secondary storage section1122 and the tertiary storage section 1123 may be configured outside thecore unit 1110 to strengthen the function of compensating for adifference in data processing speed. In another implementation, theprimary and secondary storage sections 1121, 1122 may be disposed insidethe core units 1110 and tertiary storage sections 1123 may be disposedoutside core units 1110.

The bus interface 1130 is a part which connects the core unit 1110, thecache memory unit 1120 and external device and allows data to beefficiently transmitted.

The processor 1100 according to this implementation may include aplurality of core units 1110, and the plurality of core units 1110 mayshare the cache memory unit 1120. The plurality of core units 1110 andthe cache memory unit 1120 may be directly connected or be connectedthrough the bus interface 1130. The plurality of core units 1110 may beconfigured in the same way as the above-described configuration of thecore unit 1110. In the case where the processor 1100 includes theplurality of core unit 1110, the primary storage section 1121 of thecache memory unit 1120 may be configured in each core unit 1110 incorrespondence to the number of the plurality of core units 1110, andthe secondary storage section 1122 and the tertiary storage section 1123may be configured outside the plurality of core units 1110 in such a wayas to be shared through the bus interface 1130. The processing speed ofthe primary storage section 1121 may be larger than the processingspeeds of the secondary and tertiary storage section 1122 and 1123. Inanother implementation, the primary storage section 1121 and thesecondary storage section 1122 may be configured in each core unit 1110in correspondence to the number of the plurality of core units 1110, andthe tertiary storage section 1123 may be configured outside theplurality of core units 1110 in such a way as to be shared through thebus interface 1130.

The processor 1100 according to this implementation may further includean embedded memory unit 1140 which stores data, a communication moduleunit 1150 which can transmit and receive data to and from an externaldevice in a wired or wireless manner, a memory control unit 1160 whichdrives an external memory device, and a media processing unit 1170 whichprocesses the data processed in the processor 1100 or the data inputtedfrom an external input device and outputs the processed data to anexternal interface device and so on. Besides, the processor 1100 mayinclude a plurality of various modules and devices. In this case, theplurality of modules which are added may exchange data with the coreunits 1110 and the cache memory unit 1120 and with one another, throughthe bus interface 1130.

The embedded memory unit 1140 may include not only a volatile memory butalso a nonvolatile memory. The volatile memory may include a DRAM(dynamic random access memory), a mobile DRAM, an SRAM (static randomaccess memory), and a memory with similar functions to above mentionedmemories, and so on. The nonvolatile memory may include a ROM (read onlymemory), a NOR flash memory, a NAND flash memory, a phase change randomaccess memory (PRAM), a resistive random access memory (RRAM), a spintransfer torque random access memory (STTRAM), a magnetic random accessmemory (MRAM), a memory with similar functions.

The communication module unit 1150 may include a module capable of beingconnected with a wired network, a module capable of being connected witha wireless network and both of them. The wired network module mayinclude a local area network (LAN), a universal serial bus (USB), anEthernet, power line communication (PLC) such as various devices whichsend and receive data through transmit lines, and so on. The wirelessnetwork module may include Infrared Data Association (IrDA), codedivision multiple access (CDMA), time division multiple access (TDMA),frequency division multiple access (FDMA), a wireless LAN, Zigbee, aubiquitous sensor network (USN), Bluetooth, radio frequencyidentification (RFID), long term evolution (LTE), near fieldcommunication (NFC), a wireless broadband Internet (Wibro), high speeddownlink packet access (HSDPA), wideband CDMA (WCDMA), ultra wideband(UWB) such as various devices which send and receive data withouttransmit lines, and so on.

The memory control unit 1160 is to administrate and process datatransmitted between the processor 1100 and an external storage deviceoperating according to a different communication standard. The memorycontrol unit 1160 may include various memory controllers, for example,devices which may control IDE (Integrated Device Electronics), SATA(Serial Advanced Technology Attachment), SCSI (Small Computer SystemInterface), RAID (Redundant Array of Independent Disks), an SSD (solidstate disk), eSATA (External SATA), PCMCIA (Personal Computer MemoryCard International Association), a USB (universal serial bus), a securedigital (SD) card, a mini secure digital (mSD) card, a micro securedigital (micro SD) card, a secure digital high capacity (SDHC) card, amemory stick card, a smart media (SM) card, a multimedia card (MMC), anembedded MMC (eMMC), a compact flash (CF) card, and so on.

The media processing unit 1170 may process the data processed in theprocessor 1100 or the data inputted in the forms of image, voice andothers from the external input device and output the data to theexternal interface device. The media processing unit 1170 may include agraphic processing unit (GPU), a digital signal processor (DSP), a highdefinition audio device (HD audio), a high definition multimediainterface (HDMI) controller, and so on.

FIG. 7 is an example of configuration diagram of a system implementingmemory circuitry based on an implementation of the disclosed technology.

Referring to FIG. 7, a system 1200 as an apparatus for processing datamay perform input, processing, output, communication, storage, etc. toconduct a series of manipulations for data. The system 1200 may includea processor 1210, a main memory device 1220, an auxiliary memory device1230, an interface device 1240, and so on. The system 1200 of thisimplementation may be various electronic systems which operate usingprocessors, such as a computer, a server, a PDA (personal digitalassistant), a portable computer, a web tablet, a wireless phone, amobile phone, a smart phone, a digital music player, a PMP (portablemultimedia player), a camera, a global positioning system (GPS), a videocamera, a voice recorder, a telematics, an audio visual (AV) system, asmart television, and so on.

The processor 1210 may decode inputted commands and processes operation,comparison, etc. for the data stored in the system 1200, and controlsthese operations. The processor 1210 may include a microprocessor unit(MPU), a central processing unit (CPU), a single/multi-core processor, agraphic processing unit (GPU), an application processor (AP), a digitalsignal processor (DSP), and so on.

The main memory device 1220 is a storage which can temporarily store,call and execute program codes or data from the auxiliary memory device1230 when programs are executed and can conserve memorized contents evenwhen power supply is cut off. The main memory device 1220 may includeone or more of the above-described semiconductor devices in accordancewith the implementations. For example, the main memory device 1220 mayinclude a free layer having a variable magnetization direction; a pinnedlayer having a fixed magnetization direction; and a tunnel barrier layerinterposed between the free layer and the pinned layer, wherein the freelayer may include: a first sublayer having a damping constant of 0.1 orless; a second sublayer having a perpendicular magnetic anisotropyenergy density ranging from 1.0×10⁴ to 1.0×10⁸ erg/cm³; and an insertionlayer interposed between the first sublayer and the second sublayer.Through this, data storage characteristics of the main memory device1220 may be improved. As a consequence, operating characteristics of thesystem 1200 may be improved.

Also, the main memory device 1220 may further include a static randomaccess memory (SRAM), a dynamic random access memory (DRAM), and so on,of a volatile memory type in which all contents are erased when powersupply is cut off. Unlike this, the main memory device 1220 may notinclude the semiconductor devices according to the implementations, butmay include a static random access memory (SRAM), a dynamic randomaccess memory (DRAM), and so on, of a volatile memory type in which allcontents are erased when power supply is cut off.

The auxiliary memory device 1230 is a memory device for storing programcodes or data. While the speed of the auxiliary memory device 1230 isslower than the main memory device 1220, the auxiliary memory device1230 can store a larger amount of data. The auxiliary memory device 1230may include one or more of the above-described semiconductor devices inaccordance with the implementations. For example, the auxiliary memorydevice 1230 may include a free layer having a variable magnetizationdirection; a pinned layer having a fixed magnetization direction; and atunnel barrier layer interposed between the free layer and the pinnedlayer, wherein the free layer may include: a first sublayer having adamping constant of 0.1 or less; a second sublayer having aperpendicular magnetic anisotropy energy density ranging from 1.0×10⁴ to1.0×10⁸ erg/cm³; and an insertion layer interposed between the firstsublayer and the second sublayer. Through this, data storagecharacteristics of the auxiliary memory device 1230 may be improved. Asa consequence, operating characteristics of the system 1200 may beimproved.

Also, the auxiliary memory device 1230 may further include a datastorage system (see the reference numeral 1300 of FIG. 8) such as amagnetic tape using magnetism, a magnetic disk, a laser disk usingoptics, a magneto-optical disc using both magnetism and optics, a solidstate disk (SSD), a USB memory (universal serial bus memory), a securedigital (SD) card, a mini secure digital (mSD) card, a micro securedigital (micro SD) card, a secure digital high capacity (SDHC) card, amemory stick card, a smart media (SM) card, a multimedia card (MMC), anembedded MMC (eMMC), a compact flash (CF) card, and so on. Unlike this,the auxiliary memory device 1230 may not include the semiconductordevices according to the implementations, but may include data storagesystems (see the reference numeral 1300 of FIG. 8) such as a magnetictape using magnetism, a magnetic disk, a laser disk using optics, amagneto-optical disc using both magnetism and optics, a solid state disk(SSD), a USB memory (universal serial bus memory), a secure digital (SD)card, a mini secure digital (mSD) card, a micro secure digital (microSD) card, a secure digital high capacity (SDHC) card, a memory stickcard, a smart media (SM) card, a multimedia card (MMC), an embedded MMC(eMMC), a compact flash (CF) card, and so on.

The interface device 1240 may be to perform exchange of commands anddata between the system 1200 of this implementation and an externaldevice. The interface device 1240 may be a keypad, a keyboard, a mouse,a speaker, a mike, a display, various human interface devices (HIDs), acommunication device, and so on. The communication device may include amodule capable of being connected with a wired network, a module capableof being connected with a wireless network and both of them. The wirednetwork module may include a local area network (LAN), a universalserial bus (USB), an Ethernet, power line communication (PLC), such asvarious devices which send and receive data through transmit lines, andso on. The wireless network module may include Infrared Data Association(IrDA), code division multiple access (CDMA), time division multipleaccess (TDMA), frequency division multiple access (FDMA), a wirelessLAN, Zigbee, a ubiquitous sensor network (USN), Bluetooth, radiofrequency identification (RFID), long term evolution (LTE), near fieldcommunication (NFC), a wireless broadband Internet (Wibro), high speeddownlink packet access (HSDPA), wideband CDMA (WCDMA), ultra wideband(UWB), such as various devices which send and receive data withouttransmit lines, and so on.

FIG. 8 is an example of configuration diagram of a data storage systemimplementing memory circuitry based on an implementation of thedisclosed technology.

Referring to FIG. 8, a data storage system 1300 may include a storagedevice 1310 which has a nonvolatile characteristic as a component forstoring data, a controller 1320 which controls the storage device 1310,an interface 1330 for connection with an external device, and atemporary storage device 1340 for storing data temporarily. The datastorage system 1300 may be a disk type such as a hard disk drive (HDD),a compact disc read only memory (CDROM), a digital versatile disc (DVD),a solid state disk (SSD), and so on, and a card type such as a USBmemory (universal serial bus memory), a secure digital (SD) card, a minisecure digital (mSD) card, a micro secure digital (micro SD) card, asecure digital high capacity (SDHC) card, a memory stick card, a smartmedia (SM) card, a multimedia card (MMC), an embedded MMC (eMMC), acompact flash (CF) card, and so on.

The storage device 1310 may include a nonvolatile memory which storesdata semi-permanently. The nonvolatile memory may include a ROM (readonly memory), a NOR flash memory, a NAND flash memory, a phase changerandom access memory (PRAM), a resistive random access memory (RRAM), amagnetic random access memory (MRAM), and so on.

The controller 1320 may control exchange of data between the storagedevice 1310 and the interface 1330. To this end, the controller 1320 mayinclude a processor 1321 for performing an operation for, processingcommands inputted through the interface 1330 from an outside of the datastorage system 1300 and so on.

The interface 1330 is to perform exchange of commands and data betweenthe data storage system 1300 and the external device. In the case wherethe data storage system 1300 is a card type, the interface 1330 may becompatible with interfaces which are used in devices, such as a USBmemory (universal serial bus memory), a secure digital (SD) card, a minisecure digital (mSD) card, a micro secure digital (micro SD) card, asecure digital high capacity (SDHC) card, a memory stick card, a smartmedia (SM) card, a multimedia card (MMC), an embedded MMC (eMMC), acompact flash (CF) card, and so on, or be compatible with interfaceswhich are used in devices similar to the above mentioned devices. In thecase where the data storage system 1300 is a disk type, the interface1330 may be compatible with interfaces, such as IDE (Integrated DeviceElectronics), SATA (Serial Advanced Technology Attachment), SCSI (SmallComputer System Interface), eSATA (External SATA), PCMCIA (PersonalComputer Memory Card International Association), a USB (universal serialbus), and so on, or be compatible with the interfaces which are similarto the above mentioned interfaces. The interface 1330 may be compatiblewith one or more interfaces having a different type from each other.

The temporary storage device 1340 can store data temporarily forefficiently transferring data between the interface 1330 and the storagedevice 1310 according to diversifications and high performance of aninterface with an external device, a controller and a system. Thetemporary storage device 1340 for temporarily storing data may includeone or more of the above-described semiconductor devices in accordancewith the implementations. The temporary storage device 1340 may includea free layer having a variable magnetization direction; a pinned layerhaving a fixed magnetization direction; and a tunnel barrier layerinterposed between the free layer and the pinned layer, wherein the freelayer may include: a first sublayer having a damping constant of 0.1 orless; a second sublayer having a perpendicular magnetic anisotropyenergy density ranging from 1.0×10⁴ to 1.0×10⁸ erg/cm³; and an insertionlayer interposed between the first sublayer and the second sublayer.Through this, data storage characteristics of the storage device 1310 orthe temporary storage device 1340 may be improved. As a consequence,operating characteristics and data storage characteristics of the datastorage system 1300 may be improved.

FIG. 9 is an example of configuration diagram of a memory systemimplementing memory circuitry based on an implementation of thedisclosed technology.

Referring to FIG. 9, a memory system 1400 may include a memory 1410which has a nonvolatile characteristic as a component for storing data,a memory controller 1420 which controls the memory 1410, an interface1430 for connection with an external device, and so on. The memorysystem 1400 may be a card type such as a solid state disk (SSD), a USBmemory (universal serial bus memory), a secure digital (SD) card, a minisecure digital (mSD) card, a micro secure digital (micro SD) card, asecure digital high capacity (SDHC) card, a memory stick card, a smartmedia (SM) card, a multimedia card (MMC), an embedded MMC (eMMC), acompact flash (CF) card, and so on.

The memory 1410 for storing data may include one or more of theabove-described semiconductor devices in accordance with theimplementations. For example, the memory 1410 may include may include afree layer having a variable magnetization direction; a pinned layerhaving a fixed magnetization direction; and a tunnel barrier layerinterposed between the free layer and the pinned layer, wherein the freelayer may include: a first sublayer having a damping constant of 0.1 orless; a second sublayer having a perpendicular magnetic anisotropyenergy density ranging from 1.0×10⁴ to 1.0×10⁸ erg/cm³; and an insertionlayer interposed between the first sublayer and the second sublayer.Through this, data storage characteristics of the memory 1410 may beimproved. As a consequence, operating characteristics and data storagecharacteristics of the memory system 1400 may be improved.

Also, the memory 1410 according to this implementation may furtherinclude a ROM (read only memory), a NOR flash memory, a NAND flashmemory, a phase change random access memory (PRAM), a resistive randomaccess memory (RRAM), a magnetic random access memory (MRAM), and so on,which have a nonvolatile characteristic.

The memory controller 1420 may control exchange of data between thememory 1410 and the interface 1430. To this end, the memory controller1420 may include a processor 1421 for performing an operation for andprocessing commands inputted through the interface 1430 from an outsideof the memory system 1400.

The interface 1430 is to perform exchange of commands and data betweenthe memory system 1400 and the external device. The interface 1430 maybe compatible with interfaces which are used in devices, such as a USBmemory (universal serial bus memory), a secure digital (SD) card, a minisecure digital (mSD) card, a micro secure digital (micro SD) card, asecure digital high capacity (SDHC) card, a memory stick card, a smartmedia (SM) card, a multimedia card (MMC), an embedded MMC (eMMC), acompact flash (CF) card, and so on, or be compatible with interfaceswhich are used in devices similar to the above mentioned devices. Theinterface 1430 may be compatible with one or more interfaces having adifferent type from each other.

The memory system 1400 according to this implementation may furtherinclude a buffer memory 1440 for efficiently transferring data betweenthe interface 1430 and the memory 1410 according to diversification andhigh performance of an interface with an external device, a memorycontroller and a memory system. For example, the buffer memory 1440 fortemporarily storing data may include one or more of the above-describedsemiconductor devices in accordance with the implementations. The buffermemory 1440 may include may include a free layer having a variablemagnetization direction; a pinned layer having a fixed magnetizationdirection; and a tunnel barrier layer interposed between the free layerand the pinned layer, wherein the free layer may include: a firstsublayer having a damping constant of 0.1 or less; a second sublayerhaving a perpendicular magnetic anisotropy energy density ranging from1.0×10⁴ to 1.0×10⁸ erg/cm³; and an insertion layer interposed betweenthe first sublayer and the second sublayer. Through this, data storagecharacteristics of the buffer memory 1440 may be improved. As aconsequence, operating characteristics and data storage characteristicsof the memory system 1400 may be improved.

Moreover, the buffer memory 1440 according to this implementation mayfurther include an SRAM (static random access memory), a DRAM (dynamicrandom access memory), and so on, which have a volatile characteristic,and a phase change random access memory (PRAM), a resistive randomaccess memory (RRAM), a spin transfer torque random access memory(STTRAM), a magnetic random access memory (MRAM), and so on, which havea nonvolatile characteristic. Unlike this, the buffer memory 1440 maynot include the semiconductor devices according to the implementations,but may include an SRAM (static random access memory), a DRAM (dynamicrandom access memory), and so on, which have a volatile characteristic,and a phase change random access memory (PRAM), a resistive randomaccess memory (RRAM), a spin transfer torque random access memory(STTRAM), a magnetic random access memory (MRAM), and so on, which havea nonvolatile characteristic.

Features in the above examples of electronic devices or systems in FIGS.5-9 based on the memory devices disclosed in this document may beimplemented in various devices, systems or applications. Some examplesinclude mobile phones or other portable communication devices, tabletcomputers, notebook or laptop computers, game machines, smart TV sets,TV set top boxes, multimedia servers, digital cameras with or withoutwireless communication functions, wrist watches or other wearabledevices with wireless communication capabilities.

While this patent document contains many specifics, these should not beconstrued as limitations on the scope of any invention or of what may beclaimed, but rather as descriptions of features that may be specific toparticular embodiments of particular inventions. Certain features thatare described in this patent document in the context of separateembodiments can also be implemented in combination in a singleembodiment. Conversely, various features that are described in thecontext of a single embodiment can also be implemented in multipleembodiments separately or in any suitable subcombination. Moreover,although features may be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. Moreover, the separation of various system components in theembodiments described in this patent document should not be understoodas requiring such separation in all embodiments.

Only a few implementations and examples are described. Otherimplementations, enhancements and variations can be made based on whatis described and illustrated in this patent document.

What is claimed is:
 1. An electronic device comprising a semiconductormemory, wherein the semiconductor memory includes: a free layer having avariable magnetization direction; a pinned layer having a fixedmagnetization direction; and a tunnel barrier layer interposed betweenthe free layer and the pinned layer, wherein the free layer includes: afirst sublayer having a damping constant of 0.1 or less; a secondsublayer having a perpendicular magnetic anisotropy energy densityranging from 1.0×10⁴ to 1.0×10⁸ erg/cm³; and an insertion layerinterposed between the first sublayer and the second sublayer.
 2. Theelectronic device of claim 1, wherein the second sublayer is disposedcloser to the tunnel barrier layer than the first sublayer is.
 3. Theelectronic device of claim 1, wherein the first sublayer includes aHeusler alloy, a half-Heusler alloy, or a half-metal, or a combinationthereof.
 4. The electronic device of claim 1, wherein the insertionlayer includes a material blocking crystallinity that is transferredfrom a layer disposed below the insertion layer.
 5. The electronicdevice of claim 4, wherein the insertion layer includes Zr, Hf, V, Cr,Cu, Nb, Mo, Ru, Rh, Ta, W, Re or Ir, or a combination thereof.
 6. Theelectronic device of claim 1, wherein the second sublayer includes analloy or a stack structure, which includes Co, Fe or B, or a combinationthereof.
 7. The electronic device of claim 6, wherein the secondsublayer includes a Co—Fe—B alloy or a Co—Fe—B—X alloy (where X may beMn, Cu, Al, Si, Ti, V, Cr, Ni, Ga, Ge, Zr, Nb, Mo, Pd, Ag, Hf, Ta, W orPt).
 8. The electronic device of claim 1, wherein the first sublayer hasa damping constant ranging from 0.001 to 0.1.
 9. The electronic deviceaccording to claim 1, further comprising a microprocessor whichincludes: a control unit configured to receive a signal including acommand from an outside of the microprocessor, and performs extracting,decoding of the command, or controlling input or output of a signal ofthe microprocessor; an operation unit configured to perform an operationbased on a result that the control unit decodes the command; and amemory unit configured to store data for performing the operation, datacorresponding to a result of performing the operation, or an address ofdata for which the operation is performed, wherein the semiconductormemory is part of the memory unit in the microprocessor.
 10. Theelectronic device according to claim 1, further comprising a processorwhich includes: a core unit configured to perform, based on a commandinputted from an outside of the processor, an operation corresponding tothe command, by using data; a cache memory unit configured to store datafor performing the operation, data corresponding to a result ofperforming the operation, or an address of data for which the operationis performed; and a bus interface connected between the core unit andthe cache memory unit, and configured to transmit data between the coreunit and the cache memory unit, wherein the semiconductor memory is partof the cache memory unit in the processor.
 11. The electronic deviceaccording to claim 1, further comprising a processing system whichincludes: a processor configured to decode a command received by theprocessor and control an operation for information based on a result ofdecoding the command; an auxiliary memory device configured to store aprogram for decoding the command and the information; a main memorydevice configured to call and store the program and the information fromthe auxiliary memory device such that the processor can perform theoperation using the program and the information when executing theprogram; and an interface device configured to perform communicationbetween at least one of the processor, the auxiliary memory device andthe main memory device and the outside, wherein the semiconductor memoryis part of the auxiliary memory device or the main memory device in theprocessing system.
 12. The electronic device according to claim 1,further comprising a data storage system which includes: a storagedevice configured to store data and conserve stored data regardless ofpower supply; a controller configured to control input and output ofdata to and from the storage device according to a command inputted froman outside; a temporary storage device configured to temporarily storedata exchanged between the storage device and the outside; and aninterface configured to perform communication between at least one ofthe storage device, the controller and the temporary storage device andthe outside, wherein the semiconductor memory is part of the storagedevice or the temporary storage device in the data storage system. 13.The electronic device according to claim 1, further comprising a memorysystem which includes: a memory configured to store data and conservestored data regardless of power supply; a memory controller configuredto control input and output of data to and from the memory according toa command inputted from an outside; a buffer memory configured to bufferdata exchanged between the memory and the outside; and an interfaceconfigured to perform communication between at least one of the memory,the memory controller and the buffer memory and the outside, wherein thesemiconductor memory is part of the memory or the buffer memory in thememory system.
 14. An electronic device comprising a semiconductormemory, wherein the semiconductor memory includes a variable resistanceelement, wherein the variable resistance element includes: a free layerhaving a variable magnetization direction; a pinned layer having a fixedmagnetization direction; and a tunnel barrier layer interposed betweenthe free layer and the pinned layer, wherein the free layer includes: afirst sublayer including a Heusler alloy, a half-Heusler alloy, or ahalf-metal, or a combination thereof; a second sublayer including analloy or a stack structure which includes Co, Fe or B, or a combinationthereof; and an insertion layer interposed between the first sublayerand the second sublayer.
 15. The electronic device of claim 14, whereinthe first sublayer is structured to decrease a damping constant of thefree layer.
 16. The electronic device of claim 14, wherein the secondsublayer is structured to maintain a perpendicular magnetic anisotropyenergy density of the free layer at a high level.
 17. The electronicdevice of claim 14, wherein the insertion layer includes a materialblocking crystallinity that is transferred from a layer disposed belowthe insertion layer.
 18. The electronic device of claim 17, wherein theinsertion layer includes Zr, Hf, V, Cr, Cu, Nb, Mo, Ru, Rh, Ta, W, Re orIr, or a combination thereof.
 19. The electronic device of claim 14,wherein the second sublayer includes a Co—Fe—B alloy or a Co—Fe—B—Xalloy (where, X may be Mn, Cu, Al, Si, Ti, V, Cr, Ni, Ga, Ge, Zr, Nb,Mo, Pd, Ag, Hf, Ta, W or Pt).
 20. The electronic device of claim 14,wherein the first sublayer has a damping constant ranging from 0.001 to0.1.